Su Peng, Yan Xian, Xiao Fang-Xing
College of Materials Science and Engineering, Fuzhou University, New Campus Minhou Fujian Province 350108 China.
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou Fujian 350002 P. R. China
Chem Sci. 2024 Aug 16;15(36):14778-90. doi: 10.1039/d4sc04838e.
Benefiting from their excellent light-capturing ability, suitable energy band structure and abundant active sites, transition metal chalcogenides (TMCs) have been attracting widespread attention in heterogeneous photocatalysis. Nonetheless, TMCs still suffer from sluggish charge transfer kinetics, a rapid charge recombination rate and poor stability, rendering the construction of high-performance artificial photosystems challenging. Here, a ternary dumbbell-shaped CdS/MoS/CuS heterostructure with spatially separated catalytically active sites has been elaborately designed. In such a heterostructured nanoarchitecture, MoS clusters, selectively grown on both ends of the CdS nanowires (NWs), act as terminal electron collectors, while CuS nanolayers, coated on the sidewalls of CdS NWs through ion exchange, form a P-N heterojunction with the CdS NW framework, which accelerates the migration of holes from CdS to CuS, effectively suppressing the oxidation of sulfide ions and improving the stability of CdS NWs. The well-defined dumbbell-shaped CdS/MoS/CuS ternary heterostructure provides a structural basis for spatially precise regulation of the charge migration pathway, where photogenerated electrons and holes directionally migrate to the MoS and CuS catalytic sites, respectively, ultimately achieving efficient carrier separation and significantly enhancing photoactivity for both photocatalytic hydrogen generation and selective organic transformation under visible light. Moreover, we have also ascertained that such ion exchange and interface configuration engineering strategies are universal. Our work features a simple yet efficient strategy for smartly designing multi-component heterostructures to precisely modulate spatially vectorial charge separation at the nanoscale for solar-to-hydrogen conversion.
过渡金属硫族化合物（TMCs）因其出色的光捕获能力、合适的能带结构和丰富的活性位点，在多相光催化领域受到广泛关注。然而，TMCs仍存在电荷转移动力学缓慢、电荷复合速率快和稳定性差等问题，这使得构建高性能人工光系统具有挑战性。在此，精心设计了一种具有空间分离催化活性位点的三元哑铃状CdS/MoS/CuS异质结构。在这种异质结构的纳米结构中，选择性生长在CdS纳米线（NWs）两端的MoS簇充当终端电子收集器，而通过离子交换包覆在CdS NWs侧壁上的CuS纳米层与CdS NW框架形成P-N异质结，加速了空穴从CdS向CuS的迁移，有效抑制了硫离子的氧化并提高了CdS NWs的稳定性。明确的哑铃状CdS/MoS/CuS三元异质结构为电荷迁移路径的空间精确调控提供了结构基础，其中光生电子和空穴分别定向迁移到MoS和CuS催化位点，最终实现了高效的载流子分离，并显著提高了可见光下光催化产氢和选择性有机转化的光活性。此外，我们还确定这种离子交换和界面构型工程策略具有通用性。我们的工作提出了一种简单而有效的策略，用于巧妙设计多组分异质结构，以在纳米尺度上精确调节空间矢量电荷分离，实现太阳能到氢能的转化。
